NOTES ON THE MARINE MOLLUSCA OF PORT-STEWART. 9 



*T. tenuis, Da C. — Valves fairly abundant, but not so plentiful 

 as the next species. 



*T.fabula, Gron. — " Not uncommon on extensive sandy beaches, 

 as Magilligan" (Thompson). My experience at Port- 

 Stewart was, that it was much more abundant than tenuis, 

 a circumstance the reverse of what obtains in Clyde waters. 

 Psammobia ferroensis (Chem.). — A few odd valves. "Thrown 

 up alive by the tide at Castlerock, Co. Derry." (Praeger). 



*Donax vitattus, Da C. — This is without doubt the predominant 

 shell on the coast. Some parts of the shore, e.g. the little 

 bay known as the " Ladies' Bathing Place," are literally 

 covered with the shells of this mollusc ; the shells being of 

 all hues from the richest dark purple to the most golden 

 yellow. The majority of the shells are perfect, though 

 empty, the strong ligament holding the valves together. 

 Living specimens are also frequent. Thompson states that 

 it is " plentiful close to low- water mark at Magilligan, 

 where it is collected by the people for food." Praeger 

 records it from Portrush. The only Clyde localities I have 

 for this species are : — Clyde (Smith and Landsborough — both 

 declared doubtful by Mr. Alfred Brown, and excluded 

 from his list of the mollusca of the firth) ; Ardrossan 

 and Ayr (Coulson) ; Irvine (J. Smith) ; Karnes Bay, 

 Cumbrae, one living and one dead (Robertson) ; and Salt- 

 coats (Alex. Somerville). Broad Bay, Stornoway, is the 

 great place for this shell, or rather for its variety turgida, 

 a locality where it may be seen in countless numbers. 



*D. vittatus, var. truncatus, Marsh. — I was fortunate in securing 

 three specimens of this variety, which is an addition to 

 Jeffrey's British Conchology. The shell is described and 

 figured in the Irish Naturalist for January, 1895. Mr. 

 J. T. Marshall says, that so far as he is aware, this variety 

 is peculiar to the south and west of Ireland. The discovery 

 of the variety in the extreme north of Ireland is, therefore, 

 very interesting. 



*Mactra solida, L. — By no means frequent. "Portrush, dead" 

 (Miss Richardson). " Dead valves are abundant at 

 Magilligan " (Praeger). 



M. solida, var. ettiptica, Bro. — Moderately common, 



b 



